SCCA® Solo classing — unofficial guide
What autocross class is a Honda Civic Si (10th gen)?
GSStreetGSTStreet Touring
A stock 2017–2020 Honda Civic Si (10th gen) runs in GS (Street) under the 2026 SCCA Solo Rules. Built to Street Touring allowances (within GST tire and wheel limits), it runs GST.
From the 2026 rulebook (Appendix A)
Street: 'Civic Si (2017-20)' = GS (11th gen 2022-26 also GS). ST: 'Civic Si (2017-26)' = GST; 2002-15 Si = DST.
Unofficial guidance verified against the 2026 SCCA® Solo® Rules — always confirm against the current rulebook before competing. Classing data cites the exact Appendix A wording it relies on.